The latest all new edition of the ABC 33/40 Weather Xtreme Video is available in the player below, and on iTunes.
The Storm Total Precipitation display from the NWS Doppler radar last night at 8 pm was very revealing in showing the isolated nature of the storms yesterday. Today we are likely to see a similar pattern for showers though there could be a focus across the northeastern part of the area. The reason is a large mesoscale convective complex (MCC) that was on-going this morning in the vicinity of Chattanooga that should be responsible for laying down some boundaries that will be the focus for showers and thunderstorms this afternoon.
A weak convergence zone or weak front was located across the TN/KY border, though it was very hard to find in surface data. That convergence zone is forecast to sag southward today and Sunday and should be the focus for numerous showers and thunderstorms on Sunday. Depending on the movement of that zone we may see numerous showers again on Monday.
But by Tuesday a surface low along that convergence zone should move east of Central Alabama and allow the counter-clockwise circulation to bring drier air into Central Alabama. That means that Tuesday and Wednesday should be free of showers but remain warm as highs return to the lower 90s.
Moisture should gradually return Thursday and Friday and with the moisture the possibility of scattered showers once again. While the 500 millibar pattern becomes dominated by weak high pressure, weaknesses in the ridging will still permit areas of enhanced showers. In fact, the GFS is suggesting a weak surface low along that old convergence zone. If that surface low does happen, showers and thunderstorms will be quite numerous across South Alabama as we head into the weekend. Should the convergence zone be a bit further north, Central Alabama could be the receipient of more showers. That’s getting out close to voodoo land, so we’ll just try to monitor the future model runs to see if that solution continues.
Speaking of voodoo land, the GFS is once again developing an Eastern US trough around August 9th. This sure looks like it is going to be the summer of East Coast troughs if the GFS is correct. That’s just fine by me since it keeps the heat in check for Central Alabama. The trough persists toward the end of the cycle with another tropical something or other in the Caribbean. You got to give the GFS credit for being persistent, but it is going to be right on one of these as we head into the peak of hurricane season.
I hope that everyone has a great Saturday. I’ll be filling in for Ashley this weekend so be sure to catch ABC 3340 news and weather at 6 and 10 pm this evening. Another Weather Xtreme Video should be posted by 9 am Sunday morning. God bless.
-Brian-
